Grinding machine



y 4- I H. w. LANYON 1,958,709

GRINDING MACHINE Filed Dec. 28, 1931 INVENTOR MW m m ATTO RN EYS Patented May 15, 1934 UNITED STATES PATENT? OFFICE GRINDING MACHINE Application December 28, 1931, Serial No. 583,452

6 Claims.

This invention relates to improvements in grinding machines and especially to grinding machines of the type in which the grinding element is movable over the work; the invention I more particularly relating to improvements upon the apparatus shown and described in the copending application of William A. Goering, Se-

rial No. 583,574, filed December 28, 1931.

In the Goering application there is described a machine for grinding the surfaces of track rails in which the grinding wheel is mounted upon a main frame and the main frame partly supported by a supporting member which slides upon the track rail in a manner to permit elevation of the frame and grinding wheel independently of the support. In the machine of the Goering application, in the event that the grinding wheel should strike an undue obstruction, the only relief that the wheel can secure is by an elevation of the wheel and the comparatively heavy frame which carries it.

The object of my invention is to provide means for so supporting the frame upon the sliding support that the weight of the frame will be partly counterbalanced so that the grinding wheel and the frame may more readily be elevated in order to bring the grinding wheel out of the path of undue obstruction which it may meet in the course of its operation.

A further object of the invention is to provide means for applying pressure to the grinding wheel of a grinding machine such that in the event of the wheel meeting with a sudden extraordinary load which might create a dangerous condition, the wheel will be permitted to be readily elevated with relation to the work and be again restored to normal grinding position after the undue load or obstruction has been passed.

In the accompanying drawing:

Fig. 1 is a fragmentary side elevation of an improved form of track rail surface grinder in which the principles of my invention are embodied.

Fig. 2 is an enlarged horizontal section on the line 2--2 of Fig. 1.

Fig. 3 is an enlarged, fragmentary perspective view of the device.

Referring to the drawing, in Fig. 1 is shown a portion of a frame of a grinding machine. A grinding wheel is indicated at 1, and is mounted on a spindle 2 rotatably supported in a bracket 3 secured to the frame members 4, the wheel being driven in the direction of the arrow by any suitable means (not shown). The frame is preferably mounted on flanged wheels 5 and 6 for transportation purposes and for guiding the machine during the grinding operation which is performed While the machine is being drawn along the track by any suitable means.

The frame is supported on the track wheels for transportation in the following manner. Referring to the front axle 7, an arm 8 is clamped thereto, which arm is fixed on one end of a shaft 9 which is rotatably mounted in a casting member 10 secured to the frame 4. At the other end of the shaft 9 is secured a lever 11 which extends upwardly, and is pivotally connected at the upper end to the piston rod 12 of a fluid pressure cylinder 13 which is secured to the frame. The arm 8 and the lever 11 form a bent lever and an application of fluid under pressure to the cylinder 13 to the rearward end (not shown) of the cylinder 13 causes the elevation of the frame.

The rear portion of the frame during transportation is supported in a similar manner. To the rear axle 14'is clamped an arm 15 secured to the shaft 16. The shaft 16 is rotatably mounted in a bracket 17 secured to the main frame and upon its inner end is fixed an upwardly extending lever 18. The lever 18-is pivotally connected with the piston rod 19 of the cylinder 20 secured to the frame, and application of fluid under pressure to the proper end of the cylinder 20 also results in the elevation of the frame.

To place the machine in grinding position, the pressure in the cylinders is relieved. This allows the frame to sink downwardly. The for ward portion of the frame comes to rest on the forward axle, there being a downward extension 21 of the casting member 10 so arranged to bear upon the axle. The major portion of the weight of the frame, however, during the operation of grinding is supported in the following manner:

On the upper surface of the frame directly over the center of the grinding wheel is secured a nut 22. This nut is interiorly threaded to receive a screw-threaded rod 23 which extends downwardly, and has upon its upper end a hand wheel 24. The lower end of the screw 23 is provided with a reduced-diameter extended por-- tion 25 which projects loosely into a bore in the upper central portion of a fulcrum block 26.

To the block 26 is pivotally secured the forward ends of the forks 27 of a forked lever 28 which extends rearwardly, to the free end 28 of which is secured an adjustable weight 29. The

pivotal mounting of this lever with the block 26 is by means of a pair of short pins which are inserted into the block on opposite sides at about the central portions thereof, the forked ends 27 being rotatably mounted on the projecting portions of the pins.

,A second pair of fulcrum pins 31 is employed, one each being fixed in each of the forks 27 of the lever 28 closely adjacent the openings through which the pins 30 pass. The pins 31 project outwardly from the forks 27 and each has a rotatable bearing in one bar of a pair of arch-bars 32. In the outer ends of the arch bars 32 are secured rollers 33 which bear on the upper central peripheral surface of thecircumferential rib 34 of a semi-circular supporting member 35, which is in the nature of a heavy band reenforced by the rib 34. In each of the lower free ends of the supporting member 35 is pivotally mounted one of a pair of shoes 36 and 37 which are adapted to slide upon the upper surface of the track rail 33, and are further provided with flanges 39 to facilitate guiding the machine during the grinding operation.

The supporting member is retained in a vertical plane over the track by the effect of the block 26 which is provided with a slot 40' in its lower most portion, the jaws 40 forming the slot being adapted to straddle the rib 34, and

the supporting member is also further guided by a pair of slotted guiding members 41 secured to the frame 4 in front and to the rear of the horizontal portions of the member 35.

When the pressure in the cylinders 13 and 20 is exhausted the frame sinks downwardly and is supported partly by the forward axle and partly by the shoes and other members of the adjustable supporting device just described, the arrangement for the rear axle being one in which this axle carries none of the weight of the frame.

As in the machine of the Goering application referred to, it will be seen that the grinding wheel is held to its work by the Weight of the frame upon which it is mounted, but unlike the Goering machine, a considerable portion of the weight of the main frame is counterbalanced through the arrangement described and only enough of the weight of the frame utilized'to hold the wheel to its work.

It should be clear that that portion of the weight of the machine that is transmitted to the rail surfaces is received from the screw 23, the block 26, the fulcrum pins 30 and 31, arch bars 32, rollers 33, supporting member 35 and shoes 36 and 37, and that the tendency to elevate the free end of the lever 28 is offset by placing thereon a weight of a proper size, which weight is SllfilClEl'lt to provide that the lever 28 is usually maintained at a substantially horizontal position. A stop 42 secured to the frame in position to make contact with the lever may be employed if desired, to limit the upward movement of the lever.

In operation, if the grinding wheel meets with an extraordinary load or obstruction, the tendency is to raise the wheel and frame upon which it is mounted, and since the weight of the frame upon the sliding support is partly counterbalanced by the weight, it will be seen that the grinding wheel and the frame may be more readily elevated, and after the wheel has passed over the obstruction or other condition which has caused an elevation thereof, the wheel will be automatically restored to normal grinding position.

Having thus described my invention, I claim:

1. In a grinding machine of the character described, a grinding wheel, a frame upon which said wheel is mounted, a wheeled support for one end of said frame, a second support for said frame slidably positioned on the work, said frame being capable of being elevated with relation to said second support, and means for partly counterbalancing the weight of said frame and wheel, including a lever fulcrumed upon said support, said frame being supported by said lever upon one side of the fulcrum point thereof, and a counterbalancing device connected with said lever on the other side of said fulcrum point.

2. In a grinding machine of the character described, a grinding wheel, a frame upon which said wheel is mounted, a wheeled support for one end of said frame, a second support for said frame movably positioned on the work, said frame being capable of being elevated with relation to said second support, and means for partly counterbalancing the weight of said frame and wheel, including a block to receive the weight of the frame, 'a member movably mounted upon said support, a lever fulcrumed on said member, a pivoted connection between said lever and said block on one side of the fulcrum of said lever, and a counterbalancing device carried by said lever on the other side of the fulcrum thereof.

3. In a grinding machine of the character described, a grinding wheel, a frame upon which said wheel is mounted, a support for said frame movably positioned on the work, said frame being capable of being elevated with relation to said support, and means for partly counterbalancing the weight of said frame and wheel, including I a block and adjustable screw carried by said [35 frame loosely mounted in said block, a member movably mounted on said support, a lever fulcrumed on said member, a pivoted connection between said block and said lever on one side of the fulcrum point thereof, and a weight carried by said lever on the other side of the fulcrum thereof.

4. In a grinding machine, a main frame, a wheeled support at one end of said frame on which the frame is pivotally mounted, a second support for said frame having two points of contact with the track, a grinding Wheel sup-ported by said main frame between the said two points of contact, said second support having a curvilinear supporting surface, means for movably supporting said main frame upon said curvilinear surface, said main frame also being capable of elevation independently of said support, and means for counterbalancing a part of the weight of said main frame and grinding wheel. 135

5. In a grinding machine, a main frame, a grinding wheel carried by said frame, a support for said main frame movably positioned upon the work and having a circularly-extending bearing surface, a pair of parallel bars slidably o mounted upon said circularly-extending bearing surface, a bifurcated lever having its branches fulcrumed respectively to said bars, a block located between the branches of said lever and pivotally connected therewith on one side of 4 the fulcrum point of said lever, said block receiving the weight of said main frame, and a weight carried by said lever on the other side of the fulcrum point thereof.

6. In a grinding machine, a main frame, a150 grinding Wheel carried thereby, a support movably positioned upon the Work on each side of said wheel, said support having a circularly extending bearing surface, an adjustable screw carried by said frame, a block loosely connected with the lower end of said screw, a member having friction rolls mounted upon said cir- 

